The incidence and prevalence of heart failure is increasing, especially heart failure with preserved ejection fraction (HFpEF) relative to heart failure with reduced ejection fraction (HFrEF). For both HFrEF and HFpEF, there is need to shift our focus from secondary to primary prevention. Detailed epidemiologic data on both HFpEF and HFrEF are needed to allow early identification of at-risk subjects. Current cohorts with new onset heart failure lack uniformity with respect to diagnosis, follow-up, and population characteristics, but most important, fail to distinguish between HFpEF and HFrEF. Studies on prevalent heart failure show ischemic heart disease as the predominant risk factor for HFrEF, while hypertension, atrial fibrillation, and diabetes are risk factors for HFpEF. As it becomes increasingly clear that both subtypes of heart failure are different syndromes, new cohorts and trials are necessary to obtain separate data on both subtypes of heart failure.